Biology Reference
In-Depth Information
Snowmold
Northern lawns and turf of golf greens often show
round light patches as the snow melts in early
spring. Such a disease is called snow mold and
may be due to one of several fungi, sometimes to
two appearing together.
Severity is increased by applying fertilizer in late
autumn and an excess of organic matter in the
soil. Reports differ as to susceptibility, but Colo-
nial, Washington and Metropolitan bentgrasses
appear to be more resistant then Seaside bent.
Microdochium (Fusarium)
Sclerotium
Rots
.
Fusarium nivale, Teleomorph, Monographella
nivales
Blights
.
Sclerotium rhizodes
Frost Scorch
,
String of
Pearls
, in northern states. Not exactly a
snowmold but appearing in early spring with
bleached, withered leaves covered with rows of
tiny sclerotia. Collect clippings when mowing
diseased areas to remove sclerotia on leaf tips.
▶
▶
Microdochium nivale
).
Pink
Snowmold
,
Fusarium Patch
, most important on
bentgrass on golf courses but infecting other turf
grasses and winter wheat and winter rye.
Microdochium nivale (formerly
Fusarium
nivale
, Teleomorph,
Monographella nivales
).
Pink Snowmold
,
Fusarium Patch
, most impor-
tant on bentgrass on golf courses but infecting
other turf grasses and winter wheat and winter
rye. Irregularly circular patches, from 1 to 2
inches to a foot or more, appear as snow is melt-
ing. They are whitish gray, often with a pinkish
tinge, and several patches may run together to
cover large areas. Individual plants have
a bleached appearance, feel slimy when wet.
Spores are formed in salmon-pink sporodochia
over stomata in leaves. They are sickle-shaped,
one-to three-septate. Perithecia are produced on
the luxuriant white mycelial mat.
Abundant moisture in the fall, snow falling on
unfrozen ground, deep snow, and a prolonged,
cold wet spring are predisposing factors, but the
presence of snow is not a requisite for the disease.
(see
▶
Typhula
Basidiomycetes, Aphyllophorales
Fruit body erect, simple, like a little club, on
a long stipe from a sclerotium; basidia with four
sterigmata and simple, hyaline spores.
Typhula incarnata
Snowmold
of turf and lawn
grasses,
Typhula Blight
, common in eastern
United States. As the snow disappears in spring,
a felty white mycelial mat is seen over grass and
adjacent soil. Plants wither and turn light brown
or tan in roughly circular patches, very conspic-
uous against the green of the rest of the lawn. The
chief diagnostic character is the presence of very
small, tawny to hazel brown spherical sclerotia in
